Motion picture code evaluator and billing system

ABSTRACT

A motion picture code evaluator applicable to motion picture codes such as a scalability code, PB frame code and multi-object code is to be provided. Disclosed is a motion picture code evaluator for evaluating, on a motion picture receiver for receiving via transmission means a motion picture code including a scalability code including a basic layer code and an extended layer code, the total post-transmission motion picture information amount which is based on a motion picture code loss caused by the transmission means and decoding the motion picture code, comprising, motion picture code layer separation means for separating the basic layer code and the extended layer code from the motion picture code received, basic layer loss determination means and extended layer loss determination means for respectively determining a loss of the basic layer code and the extended layer code separated by the motion picture code layer separation means, and motion picture code evaluation means for evaluating the total post-transmission motion picture information in accordance with the outputs of the basic layer loss determination means and the extended layer loss determination means.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a motion picture code evaluator and inparticular to a motion picture code communications evaluation technologyto simultaneously evaluate and test the motion picture quality ofdigital motion picture data transmitted in parallel to a large number ofusers by using a scalability code.

2. Description of Related Art

A related art technology concerning a motion picture code communicationsevaluator for evaluating the motion picture quality of transmitteddigital motion picture data is disclosed in the Japanese PatentApplication No. 2001-049544 “A motion picture communications evaluatorand related systems” by the same inventor.

The related art technology will be summarized insofar as it is relatedto the invention.

A digital motion picture is a continuous sequence of instantaneouspictures in time called motion picture frames.

Data of a digital motion picture is generally huge. Thus, motion picturecode transmission is generally performed where compression or encodingof information is made for data communications, followed by a decodingprocess to regenerate a motion picture. A sequence of motion codes isalso called a stream.

A scalability code refers to a method for transmitting codes inhierarchical form to input only codes fit for the processing scale ofthe receiver or only those fit for the transmission path when there area variety of receivers and transmission path scales.

Specific examples will be given later.

For example, international standards for motion picture codes includes,for example, MPEG (Moving Picture Experts Group)-2 (ISO/IEC13818) andMPEG-4 (ISO/IEC14496) specified by ISO/IEC (International organizationfor Standardization/International Electrotechnical Commission), andH.263 specified by ITU (International Telecommunication Union)recommendations.

The invention is applicable to similar motion picture codes as well asthe international standards.

In the aforementioned motion picture code, frames comprise pixelsarranged in a shape of a grating. A format comprising 352 pixels in thehorizontal direction and 288 pixels in the vertical direction are oftenused.

The number of pixels which constitute a frame is also called resolutionor a screen size.

In the case of a color image, the number of pixels is often referred toas the structure of a luminance screen (Y).

Colors and gray-scale levels in a color image are often represented as aluminance and two types of color difference values to represent colors.

A format which assigns two color difference pixels per luminance of twoby two pixels or one which assigns four difference pixels are available.

The number of frames per unit time may be 30 frames per second or 15frames per second. The greater this figure is, the smoother motion isrepresented, that is, the higher-quality picture is obtained.

The greater the number of pixels per frame is, the higher-resolutionmotion picture is obtained. The greater the number of pixels per unittime is, the smoother motion picture, or higher-resolution motionpicture is obtained. However, this results in a greater load on atransmission path, transmitter or receiver.

This problem is solved by a motion picture communications method wherebythe resolution is increased or decreased by twice or four times in themidst of transmission in order to keep up with a change in thesubstantial throughput caused by network congestion or radio wavepropagation.

In terms of representation of colors and gray-scale levels in digitalvalues, intermediate halftones from the darkest black to the lightestwhite are quantized. In general applications, levels in the neighborhoodof 256-level gray scale which can be visually represented in eight bitsare often used.

An image with a smaller change in gray-scale levels can be representedby a smaller number of gray-scale levels. For a color image, the numberof quantization levels is the number of colors unless otherwisespecified.

The greater the number of gray-scale levels or colors is, thehigher-quality picture is obtained although this places a greater loadon a transmission path, transmitter or receiver. This problem is solvedby extending the width of quantization thus reducing the number ofgray-scale levels.

A change in the number of gray-scale levels is often made even within asingle frame.

Talking of a certain pixel, the narrower the quantization width is, thatis, the greater the number of gray-scale levels or colors is, the moreinformation is included.

The total sum value of the number of gray-scale quantization levelswithin a specified period across the pixels in all the frames is calledthe motion picture information amount here.

Roughly speaking, the larger the motion picture information amount is,the higher-quality picture is obtained.

As far as the compression ratio of motion picture encoding does notnoticeably vary, the wider the band of a motion code is, the larger themotion picture information amount is, thus the higher-quality picture isobtained. This results in a greater load on a transmission path,transmitter or receiver. A method for operating a service with a highcharge may be used to offset this drawback.

Charging on the basis of the occupied bandwidth and occupied timefocuses on the cost of transmission path and transmission equipmentwhile charging on the basis of the motion picture information amountfocuses on the quality of an application. The latter method isimportance because it likely to gain the consensus of users.

Quality degradation of a motion picture in the course of transmission ofa motion picture code will be described.

In communications of a motion picture code, the receiving party obtainsa lower quality picture than the original for the following reasons:

A transmission error may prevent a motion picture code from beingproperly received.

Some packets may be lost halfway as a result of data transmission inpackets.

Communications of motion picture codes may take excessive time. Anencoded motion picture frame may not be ready for display at the timingof the display in the ongoing motion picture playback. In this case,display of the motion picture frame is skipped to shift to theprocessing of the next motion picture frame.

In this way, a section which failed to display an encoded picture of theoriginal motion picture is called a loss of motion picture.

A transmission error has different effects on the decoded motion pictureto be displayed, depending on the section where the error has takenplace.

A section which accommodates parameters to represent the specificationsfor the entire motion picture codes such as the screen size of a motionpicture code and a color difference format as well as codes used in thepredictive encoding system and prediction method for the entire frame iscalled a header.

In case a transmission error has occurred in the header section, theentire motion picture may be seriously affected or display of the entiredecoded frame may be disabled.

In case a transmission error has occurred in a section concerning thegray-scale level of pixels in a frame, display of the decoded pixel maybe disabled.

In this way, the amount of motion picture codes not used for display ofdecoded pictures due to a transmission error and a delay and the amountof loss of a decoded motion picture are not in a fixed relationship.Thus, a loss of the motion picture must be evaluated on demand.

However, calculating the motion picture information amount and motionpicture loss amount each time motion codes are received on all thereceivers will require a huge processing scale.

In particular, processing to decode a motion picture and reproduce apicture involves a huge workload. Thus, in practice, only limitedsections are read such as the header of a motion picture code forfurther processing.

Actually, an effective motion picture quality check is conducted beforestarting a service. This check includes a server load test whichverifies whether a motion picture server or cache server can transmitquality motion pictures in response to multiple access by a large numberof users and a motion picture quality probing (temporarily called) whichcaptures motion codes for degradation in a concentrator where motioncodes destined for a large number of users flow on the same transmissionpath, for example just after the codes have left the motion pictureserver.

In this way, the Japanese Patent Application No. 2001-049544 “A motionpicture communications evaluator and related systems” by the sameinventor provides an apparatus for evaluating the motion pictureinformation amount and motion picture loss amount.

A configuration example will be explained referring to a motion picturecode evaluator 501 of FIG. 5.

The motion picture code evaluator 501 shows the configuration ofapparatus which inputs and detects a motion picture code for a specificuser. In the example, a motion picture is not decoded or a picture isnot reproduced. Thus, motion picture codes destined for a large numberof users are simultaneously processed.

In FIG. 5, a header tester 52 extracts a motion picture frame header. Incase any error is detected, the header tester 52 determines thecorresponding frame as a loss. In case no error is detected, the headertester 52 reads the time stamp. In case a delay is detected, the headertester 52 determines the frame as a loss.

A screen size extractor 53 reads the screen size. A frame rate extractor54 reads the frame rate or converts the timing of the frames and numberof frame headers within a certain period. A quantization roughnessextractor 55 reads the quantization roughness.

A motion picture information calculator 51 obtains the number ofgray-scale levels from the quantization roughness and sums up the numberof gray-scale levels for all the pixels across the frames.

The motion picture information amount of a frame assumed as a loss isnot added. In case the predicted number of frames cannot be read fromthe frame rate, a frame loss is assumed. The frame loss determined froman error in a motion picture frame header is added to this frame lossand the resulting frame loss is divided by the predicted number offrames to obtain a frame loss ratio.

The motion picture information calculator 51 provides the loss/normalitycheck result of each frame, motion picture information amount, number ofmotion picture frames, and motion picture code amount as an output 503.Although not detailed, these data are summed across the motion pictureframes within the evaluation range.

In the Japanese Patent Application No. 2001-391370 “Motion picturedelivery test apparatus” by the same inventor, the predicted type ofeach frame is read by a motion picture frame predicted type section, andother frames referencing a frame determined as a frame loss are alsoassumed as frame losses by reference-non-reference relationship of theframes and added to the aforementioned number of frame losses.

The aforementioned motion picture code is generated in the course offrame-based encoding of a motion picture comprising a sequence of motionpicture frames on a single screen. In the motion picture stream thusgenerated, codes related to a motion picture frame are arranged in theform of a motion picture frame header and a motion picture frame datasection in this order. This structure is repeated in the order of motionpicture frame sequences. This is called a single video layer code here.

A motion picture frame may comprise a plurality of codes: an encodedsimple image of poor quality and an encoded difference between theoriginal picture and the image of poor quality.

This structure is called a scalability code as mentioned earlier.

FIG. 2 shows an example of a scalability code relating to resolution. Amotion picture with smaller number of pixels, that is, a high-resolutionmotion picture is encoded as a basic low-resolution layer motion pictureand the extended layer motion picture corresponding to the differencefrom the original. In a decoding process, by adding a motion pictureobtained by decoding the extended layer code to the basic layer motionpicture obtained by decoding the basic layer code, a high-quality motionpicture is obtained.

A plurality of subjects may be respectively encoded. In this case, asingle screen is obtained by synthesizing the subjects obtained bydecoding the subjects encoded.

This is called a multi-object code. Digitized form of each subject iscalled a video object.

Two adjacent motion picture frames may be encoded in one operation,which is an encoding system called a PB frame mode.

In this encoding system, frames can be inserted with a smaller number ofcodes thus allowing smoother motion.

The aforementioned MPEG-2, MPEG-4 and H.263 specify the scalability codeas follows:

A motion picture with a greater quantization width and a smaller numberof gray-scale levels is assumed as a basic motion picture. Encodingresult of a basic motion picture is called a basic stream. Encodingresult of the difference between the original high-quality motionpicture and the basic motion picture is called an extended stream.

For example, in a system for transmitting a signal by modulating acarrier wave, the basic stream includes a signal obtained by modulatinga carrier wave at a low frequency while the extended stream includes asignal obtained by modulating the carrier wave at a high frequency. Alow-cost terminal obtains a basic motion picture by demodulating only alow-frequency modulated signal to decode the basic stream, while ahigh-cost terminal obtains the original high-quality motion picture bymodulating a high-frequency modulated signal also to decode the extendedstream and adding the extended stream to the basic motion picture.

The H.263 specifies the PB frame mode where adjacent frames are encodedin one operation.

In H.263 and MPEG-2, a frame is also referred to as a Picture, andhereinafter treated as such.

In MPEG-4, the pixel size, frame rate and width of quantization arespecified per plurality of video object. How each object synthesizes thescreen is also specified.

Whether the scalability code is applied or not is determined per object.

In MPEG-4, the motion picture frame of each video object is called aplane or Video Object Plane (VOP).

The scalability code in MPEG-2, MPEG-4 and H.263, PB frame mode inH.263, and multi-object code in MPEG-4 are not mandatory but may beselected to be used or not used.

In the related art method, it is not possible to evaluate in parallelthe motion picture quality of a plurality of streams other than thoseincluding a single video layer code.

SUMMARY OF THE INVENTION

An object of the invention is to provide a motion picture code evaluatorapplicable to motion picture codes such as a scalability code, PB framecode and multi-object code.

In order to solve the problems, a first aspect of the invention providesa motion picture code evaluator for evaluating, on a motion picturereceiver for receiving via transmission means a motion picture codecomprising a scalability code including a basic layer code and anextended layer code, the total post-transmission motion pictureinformation amount which is based on a motion picture code loss causedby the transmission means and decoding the motion picture code,comprising,

motion picture code-layer separation means for separating the basiclayer code and the extended layer code from the motion picture codereceived, basic layer loss determination means and extended layer lossdetermination means for respectively determining a loss of the basiclayer code and the extended layer code separated by the motion picturecode layer separation means, and motion picture code evaluation meansfor evaluating the total post-transmission motion picture informationamount in accordance with the outputs of the basic layer lossdetermination means and the extended layer loss determination means.

A second aspect of the invention provides a motion picture codeevaluator comprising,

in the determination by the basic layer loss determination means, atotal motion picture information amount is set to zero for a basic layerloss, while in the determination by the extended layer lossdetermination means, the motion picture information amount of the basiclayer is employed as a total motion picture information amount for anextended layer loss and that in case the determination by the basiclayer loss determination means and the extended layer loss determinationmeans has detected no losses, a weight which is based on the frame timeinterval after synthesis of the basic layer and extended layer is usedto obtain the sum value the motion picture information amount in theframes, which sum value is employed as a total motion pictureinformation amount, the motion picture information amount of either thebasic layer or extended layer of whichever the resolution is higher isemployed as a total motion picture information amount, or thequantization roughness of either the basic layer or extended layer ofwhichever the quantization roughness is finer is used and the motionpicture information amount obtained by adding the number of gray-scalelevels across the number of pixels of the extended layer is employed asa total motion picture information amount.

A third aspect of the invention provides a motion picture code evaluatorfor evaluating, on a motion picture receiver for receiving viatransmission means a motion picture code comprising a scalability codeincluding a basic layer code and an extended layer code, the totalpost-transmission motion picture information amount which is based on amotion picture code loss caused by the transmission means and decodingthe motion picture code, comprising,

motion picture code layer separation means for separating the basiclayer code and the extended layer code from the motion picture codereceived, basic layer loss determination means for determining a loss ofthe basic layer code separated by the motion picture code layerseparation means, and motion picture code evaluation means forevaluating the total post-transmission motion picture information amountin accordance with the output of the basic layer loss determinationmeans.

A fourth aspect of the invention provides a motion picture codeevaluator for evaluating, on a motion picture receiver for receiving viatransmission means a PB frame mode motion picture code, the totalpost-transmission motion picture information amount which is based on amotion picture code loss caused by the transmission means and decodingthe PB frame mode motion picture code, comprising,

header test means for checking the frame header of PB frames of a motionpicture code in the PB frame mode for normality or loss, screen sizeextraction means and frame rate extraction means for respectivelyreading the screen size and number of frames of the PB frames from thePB frame header, Picture P quantization roughness extraction means forreading the Picture P quantization roughness of the PB frames from thePB frame header, Picture B quantization roughness extraction means forreading the Picture B quantization roughness of the PB frames from thePB frame header, Picture P motion picture information amount calculationmeans for calculating the Picture P motion picture information amountfrom the screen size and the Picture P quantization roughness, Picture Bmotion picture information amount calculation means for calculating thePicture B motion picture information amount from the screen size and thePicture B quantization roughness, and

totals the motion picture information amount of normal frames from theresult of determination of the number of frames and the frame loss, andemploys the resulting motion picture information amount as a totalmotion picture information amount.

A fifth aspect of the invention provides a motion picture code evaluatorfor evaluating, on a motion picture receiver for receiving viatransmission means a motion picture code comprising a multi-object code,the total post-transmission motion picture information amount which isbased on a motion picture code loss caused by the transmission means anddecoding the motion picture code, comprising,

a plurality of motion picture information amount calculation means forcalculating the motion picture information amount per object included ina frame of a received motion picture code comprising a multi-object codeand

totals the outputs of the motion picture information amount calculationmeans modified by a weight per object and employs the total value as atotal motion picture information amount.

A sixth aspect of the invention provides a multiple motion picturestream evaluator comprising a plurality of motion picture codeevaluators according to any one of the first through fifth aspects,arranged to process a plurality of motion picture streams in parallel.

A seventh aspect of the invention provides a billing system for a motionpicture transmission service which charges depending on the receivingquality of a motion picture based on the total motion pictureinformation amount obtained from a motion picture code evaluatoraccording to any one of the first through sixth aspects.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram showing the configuration of a motion picturecode evaluator according to a first embodiment of the invention;

FIG. 2 is an explanatory drawing which shows an example of a scalabilitycode;

FIG. 3 is a block diagram showing the configuration of a motion picturecode evaluator according to a second embodiment of the invention;

FIG. 4 is a block diagram showing the configuration of a motion picturecode evaluator according to a third embodiment of the invention; and

FIG. 5 is a block diagram showing the configuration of a motion picturecode evaluator according to the related art (reference).

DESCRIPTION OF THE PREFERRED EMBODIMENTS

An embodiment of the invention will be described referring to thedrawings.

FIG. 1 is a block diagram showing the configuration of a motion picturecode evaluator to address the scalability code.

In FIG. 1, a motion picture code transmitter 11 transmits a scalabilitycode.

A motion picture code evaluator 101 comprises a motion picture codelayer separator 102, a basic layer motion picture code evaluator 111, anextended layer motion picture code evaluator 112 and a total motionpicture information amount calculator/evaluator 100. The total motionpicture information amount calculator/evaluator 100 outputs the totallayer frame loss/normality information, total motion picture informationamount and code amount.

A motion picture code layer separator 102 receives a motion picture codecomprising a scalability code transmitted from the motion picture codetransmitter 11 and outputs the basic layer code to a basic layer motionpicture code evaluator 111 and the extended layer code to an extendedlayer motion picture code evaluator 112, respectively.

The basic layer motion picture code evaluator 111 and the extended layermotion picture code evaluator 112 check the motion picture frame headerof each layer.

In case the length of the motion picture frame header is incorrect, anumeric value exceeding the acceptable range is obtained when aparameter is read, or the time code to be decoded and displayed is founddelayed from the specified time when the time code is read, the motionpicture frame of the layer is determined as a loss.

The basic layer motion picture code evaluator 111 and the extended layermotion picture code evaluator 112 then calculates the motion pictureinformation amount of each layer.

This process is the same as that in the motion picture code evaluator501.

Next, the total motion picture information amount calculator/evaluator100 outputs the motion picture information amount, frame normality/lossinformation and code amount of the basic layer and the extended layer.

In case the basic layer is a loss, the total motion picture informationamount is zero.

In case the basic layer is normal and extended layer is a loss, thetotal motion picture information amount of the basic layer is employedas a total motion picture information amount.

In case both the basic layer and the extended layer are normal, theinformation amount to be obtained is the motion picture informationamount of a motion picture obtained after synthesis of all layers. Thetotal motion picture information amount is calculated from the motionpicture code of each layer without using decoding or synthesis, by usingthe following method:

For a time scalability extended layer, that is, in case the extendedlayer adds a frame between frames of a lower-rank layer, the weight ofthe motion picture information amount of each layer is summed as aweight proportional to the time to next frame based on the frame timeinterval after the frame has been added. The sum value is employed as atotal motion picture information amount.

In case the next frame is a loss, the time to the lost frame is employedas a weight. Two methods are available: from the lost frame to nextnormal frame, the motion picture information amount is zero, or the timeto the earliest normal frame is used as a weight assuming that theimmediately preceding normal frame continues during the period of loss.

For the latter, another method obtains the frame loss ratio of aspecific period after calculating the total motion picture informationamount of the period and multiplies the total motion picture informationamount by (1-frame loss ratio) to correct the initial amount.

Which method to use may be determined depending on the situation, suchas the calculation cost and the accuracy of motion picture informationamount.

In case the frame rate is constant and an extended layer is insertedbetween just in the center between basic layer frames, the sum of themotion picture information amount of the basic layer and the motionpicture information amount of the extended layer may be employed as atotal motion picture information amount.

Next, how to calculate the total motion picture information amount forthe space scalability extended layer will be explained.

In this method, a low-resolution image in the basic layer of a frame ata certain time is synthesized with a differential image with a highresolution in the extended layer. The resulting number of pixels aftersynthesis is the number of pixels in the extended layer.

The information amount of a specific pixel after synthesis is the numberof gray-scale levels obtained from the quantization roughness of eitherthe basic layer or extended layer whichever is finer.

The total sum of the number of gray-scale levels calculated across allpixels after synthesis is employed as a total motion picture informationamount.

Another method simply assumes the motion picture information amount ofthe extended layer as a total motion picture information amount in casethe number of pixels after synthesis is equal to the number of pixels inthe extended layer, assuming that the quantization roughness of theextended layer is less likely to be coarser than the basic layer.

Which method to use may be determined depending on the situation, suchas the calculation cost and the accuracy of motion picture informationamount.

Next, how to calculate the total motion picture information amount forthe SNR scalability extended layer will be explained.

In this method, an image with coarse quantization in the basic layer issynthesized with a differential image of extended layer with finequantization. The information amount of a specific pixel after synthesisis the number of gray-scale levels obtained from the quantizationroughness of either the basic layer of extended layer whichever isfiner.

The total sum of the number of gray-scale levels calculated across allpixels after synthesis is employed as a total motion picture informationamount.

Another method simply assumes the motion picture information amount ofthe extended layer as a total motion picture information amount sincethe number of pixels after synthesis is equal to the number of pixels inthe extended layer, assuming that the quantization roughness of theextended layer is less likely to be coarser than the basic layer.

Which method to use may be determined depending on the situation, suchas the calculation cost and the accuracy of motion picture informationamount.

As far as the evaluation is on the basic layer alone, the output of thebasic layer motion picture code evaluator 111 maybe employed as a totalmotion picture information amount.

In case a plurality of motion picture streams are to be simultaneouslyevaluated, as many number of motion picture code evaluators 101 as thenumber of motion picture streams may be provided for later parallelprocessing.

In the case of a parallel processing using a computer, a motion picturecode may be buffered in the process.

Decoding of a motion picture code or regeneration of an image does nottake place in this case, so that a general computer may be used for thispurpose.

This is the end of explanation on the embodiment concerning thescalability code.

FIG. 3 is a block diagram showing the configuration of a motion picturecode evaluator in the PB frame mode.

In FIG. 3, a motion picture code transmitter 11 transmits a motionpicture code, a PB frame mode motion picture code in this example.

A header tester 32 extracts a motion picture frame header from the PBframe mode motion picture code received on a motion picture codereceiver 302. In case any error is detected, the header tester 32determines the corresponding motion picture frame as a loss. In case noerror is detected, the header tester 32 reads the time stamp. In case adelay is detected, the header tester 32 determines the frame as a loss,and the two PB frames if any as a loss.

In case another Picture referenced by Picture P or Picture B is a loss,a frame loss is assumed.

A screen size extractor 33 reads the screen size from the frame headerdetected in header detector 32. A frame rate extractor 34 reads theframe rate from the frame header detected in header detector 32 orconvert the frame rate from the timing of frame within certain periodand number of frame header.

A quantization roughness extractor 351 reads the quantization roughnessof Picture P. A quantization roughness extractor 352 reads thequantization roughness of Picture B.

Processing including the header test and screen size/frame processing iscommon between the two frames. A detected signal is processed by apicture common processor 37.

The motion picture information amount of Picture P is obtained bysumming the number of gray-scale levels of Picture P across all pixelson a Picture P motion picture information amount calculator 311.

Similarly, the motion picture information amount of Picture B isobtained by summing the number of gray-scale levels of Picture B acrossall pixels on a Picture B motion picture information amount calculator312.

As an output 303 of a motion picture code evaluator 301, theloss/normality check result, motion picture information amount, numberof motion picture frame losses and motion picture code amount of the twoframes are obtained.

Although not shown, these data are summed across the motion pictureframe within the evaluation range.

In case a plurality of motion picture streams are to be simultaneouslyevaluated, as many motion picture code evaluators 301 as the number ofmotion picture streams may be provided for later parallel processing, asin the previous example.

In the case of a parallel processing using a computer, a motion picturecode may be buffered in the process.

In this case also, decoding of a motion picture code or regeneration ofan image does not take place, so that a general computer may be used forthis purpose.

This is the end of explanation on the embodiment concerning the PB framemode.

FIG. 4 is a block diagrams showing the internal configuration of amotion picture code evaluator to address the multi-object code.

For example, in a motion picture comprising three video objects, in casea frame comprises VOP-1, VOP-2 and VOP-3, a motion picture informationamount 411 of VOP-1, a motion picture information amount 412 of VOP-2and a motion picture information amount 413 of VOP-3 are input to atotal motion picture information amount processor 400.

The total motion picture information amount processor 400 calculates themotion picture information amount of each VOP, sum of the motion pictureinformation amount per video object and corrects the result with aweight of the video object to obtain a total motion picture informationamount which is based on the weighted sum, and provides the resultingvalue at an output 403.

In case a plurality of motion picture streams are to be simultaneouslyevaluated, as many motion picture code evaluators in FIG. 4 as thenumber of motion picture streams may be provided for later parallelprocessing, as in the previous example.

In the case of a parallel processing using a computer, a motion picturecode may be buffered in the process.

In this case also, decoding of a motion picture code or regeneration ofan image does not take place, so that a general computer may be used forthis purpose.

In case a single layer code, scalability code, PB frame mode andmulti-object code are included in a plurality of motion picture streams,motion picture code evaluators corresponding to these codes are used toperform parallel processing.

A motion picture code evaluator is provided for load test for number ofreal time users of motion picture streaming system and streaming qualitycheck of the motion picture streaming service for multiple users.

For example, it is possible to perform billing according to thereceiving quality of a motion picture based on the total motion pictureinformation amount from the motion picture code evaluator shown in FIGS.1, 3 and 4.

The first aspect of the invention provides a motion picture codeevaluator for evaluating, on a motion picture receiver for receiving viatransmission means a motion picture code comprising a scalability codeincluding a basic layer code and an extended layer code, the totalpost-transmission motion picture information amount which is based on amotion picture code loss caused by the transmission means and decodingthe motion picture code, comprising,

motion picture code layer separation means for separating the basiclayer code and the extended layer code from the motion picture codereceived, basic layer loss determination means and extended layer lossdetermination means for respectively determining a loss of the basiclayer code and the extended layer code separated by the motion picturecode layer separation means, and motion picture code evaluation meansfor evaluating the total post-transmission motion picture information inaccordance with the outputs of the basic layer loss determination meansand the extended layer loss determination means. This makes it possibleto provide a motion picture code evaluator which evaluates the motionpicture information amount, motion picture frame loss and code amount ofa scalability code.

The second aspect of the invention provides a motion picture codeevaluator comprising,

in the determination by the basic layer loss determination means, atotal motion picture information amount is set to zero for a basic layerloss, while in the determination by the extended layer lossdetermination means, the motion picture information amount of the basiclayer is employed as a total motion picture information amount for anextended layer loss and that in case the determination by the basiclayer loss determination means and the extended layer loss determinationmeans has detected no losses, a weight which is based on the frame timeinterval after synthesis of the basic layer and extended layer is usedto obtain the sum value the motion picture information amount in theframes, which sum value is employed as a total motion pictureinformation amount, the motion picture information amount of either thebasic layer or extended layer of whichever the resolution is higher isemployed as a total motion picture information amount, or thequantization roughness of either the basic layer or extended layer ofwhichever the quantization roughness is finer is used and the motionpicture information amount obtained by adding the number of gray-scalelevels across the number of pixels of the extended layer is employed asa total motion picture information amount.

The third aspect of the invention provides a motion picture codeevaluator for evaluating, on a motion picture receiver for receiving viatransmission means a motion picture code comprising a scalability codeincluding a basic layer code and an extended layer code, the totalpost-transmission motion picture information amount which is based on amotion picture code loss caused by the transmission means and decodingthe motion picture code, comprising,

motion picture code layer separation means for separating the basiclayer code from the motion picture code received, basic layer lossdetermination means for determining a loss of the basic layer codeseparated by the motion picture code layer separation means, and motionpicture code evaluation means for evaluating the total post-transmissionmotion picture information in accordance with the output of the basiclayer loss determination means. This makes it possible to evaluate themotion picture information amount, motion picture frame loss and codeamount of a code including a scalability frame code.

The fourth aspect of the invention provides a motion picture codeevaluator for evaluating, on a motion picture receiver for receiving viatransmission means a PB frame mode motion picture code, the totalpost-transmission motion picture information amount which is based on amotion picture code loss caused by the transmission means and decodingthe PB frame mode motion picture code, comprising,

header test means for checking the frame header of PB frames of a motionpicture code in the PB frame mode for normality or loss, screen sizeextraction means and frame rate extraction means for respectivelyreading the screen size and number of frames of the PB frames from thePB frame header, Picture P quantization roughness extraction means forreading the Picture P quantization roughness of the PB frames from thePB frame header, Picture B quantization roughness extraction means forreading the Picture B quantization roughness of the PB frames from thePB frame header, Picture P motion picture information amount calculationmeans for calculating the Picture P motion picture information amountfrom the screen size and the Picture P quantization roughness, Picture Bmotion picture information amount calculation means for calculating thePicture B motion picture information amount from the screen size and thePicture B quantization roughness, and

totals the motion picture information amount of normal frames from theresult of determination of the number of frames and the frame loss, andemploys the resulting motion picture information amount as a totalmotion picture information amount. This makes it possible to evaluatethe motion picture information amount, motion picture frame loss andcode amount of a code including PB frames.

The fifth aspect of the invention provides a motion picture codeevaluator for evaluating, on a motion picture receiver for receiving viatransmission means a motion picture code comprising a multi-object code,the total post-transmission motion picture information amount which isbased on a motion picture code loss caused by the transmission means anddecoding the motion picture code, comprising,

a plurality of motion picture information amount calculation means forcalculating the motion picture information amount per object included ina frame of a received motion picture code comprising a multi-object codeand

totals the outputs of the motion picture information amount calculationmeans modified by a weight per object and employs the total value as atotal motion picture information amount. This makes it possible toevaluate the motion picture information amount, motion picture frameloss and code amount of a multi-object code.

The sixth aspect of the invention provides a multiple motion picturestream evaluator comprising a plurality of motion picture codeevaluators according to any one of the first through fifth aspects,arranged to process a plurality of motion picture streams in parallel.Image regeneration does not take place so that it is possible tosimultaneously evaluate a plurality of motion picture streams.

The seventh aspect of the invention provides a billing system for amotion picture transmission service which charges depending on thereceiving quality of a motion picture based on the total motion pictureinformation amount obtained from a motion picture code evaluatoraccording to any one of the first through sixth aspects. This implementsan optimum billing system for a motion picture transmission service onthe basis of the receiving quality of a motion picture.

What is claimed is:
 1. A motion picture code evaluator for evaluating,on a motion picture receiver for receiving via transmission means amotion picture code comprising a scalability code including a basiclayer code and an extended layer code, the total post-transmissionmotion picture information amount which is based on a motion picturecode loss caused by said transmission means and decoding said motionpicture code, comprising, motion picture code layer separation means forseparating the basic layer code and the extended layer code from themotion picture code received, basic layer loss determination means andextended layer loss determination means for respectively determining aloss of the basic layer code and the extended layer code separated bysaid motion picture code layer separation means, and motion picture codeevaluation means for evaluating the total post-transmission motionpicture information amount in accordance with the outputs of said basiclayer loss determination means and said extended layer lossdetermination means.
 2. A motion picture code evaluator according toclaim 1, comprising, in the determination by said basic layer lossdetermination means, a total motion picture information amount is set tozero for a basic layer loss, while in the determination by said extendedlayer loss determination means, the motion picture information amount ofthe basic layer is employed as a total motion picture information amountand that in case the determination by said basic layer lossdetermination means and said extended layer loss determination means hasdetected no losses, a weight which is based on the frame time intervalafter synthesis of the basic layer and extended layer is used to obtainthe sum value the motion picture information amount in the frames, whichsum value is employed as a total motion picture information amount, themotion picture information amount of either the basic layer or extendedlayer of whichever the resolution is the higher is employed as a totalmotion picture information amount, or the quantization roughness ofeither the basic layer or extended layer of whichever the quantizationroughness is the finer is used and the motion picture information amountobtained by adding the number of gray-scale levels across the number ofpixels of the extended layer is employed as a total motion pictureinformation amount.
 3. A motion picture code evaluator for evaluating,on a motion picture receiver for receiving via transmission means amotion picture code comprising a scalability code including a basiclayer code and an extended layer code, the total post-transmissionmotion picture information amount which is based on a motion picturecode loss caused by said transmission means and decoding said motionpicture code, comprising, motion picture code layer separation means forseparating the basic layer code and extended layer code from the motionpicture code received, basic layer loss determination means fordetermining a loss of the basic layer code separated by said motionpicture code layer separation means, and motion picture code evaluationmeans for evaluating the total post-transmission motion pictureinformation amount in accordance with the output of said basic layerloss determination means.
 4. A motion picture code evaluator forevaluating, on a motion picture receiver for receiving via transmissionmeans a PB frame mode motion picture code, the total post-transmissionmotion picture information amount which is based on a motion picturecode loss caused by said transmission means and decoding said PB framemode motion picture code, comprising, header test means for checking theframe header of PB frames of a motion picture code in the received PBframe mode for normality or loss, screen size extraction means and framerate extraction means for respectively reading the screen size andnumber of frames of the PB frames from said PB frame header, Picture Pquantization roughness extraction means for reading the Picture Pquantization roughness of the PB frames from said PB frame header,Picture B quantization roughness extraction means for reading thePicture B quantization roughness of the PB frames from said PB frameheader, Picture P motion picture information amount calculation meansfor calculating the Picture P motion picture information amount fromsaid screen size and the Picture P quantization roughness, Picture Bmotion picture information amount calculation means for calculating thePicture B motion picture information amount from said screen size andthe Picture B quantization roughness, and totals the motion pictureinformation amount of normal frames from the result of determination ofsaid number of frames and said frame loss, and employs the resultingmotion picture information amount as a total motion picture informationamount.
 5. A motion picture code evaluator for evaluating, on a motionpicture receiver for receiving via transmission means a motion picturecode comprising a multi-object code, the total post-transmission motionpicture information amount which is based on a motion picture code losscaused by said transmission means and decoding said motion picture code,comprising, a plurality of motion picture information amount calculationmeans for calculating the motion picture information amount per objectincluded in a frame of a received motion picture code comprising amulti-object code and totals the outputs of said motion pictureinformation amount calculation means modified by a weight per object andemploys the total value as a total motion picture information amount. 6.A multiple motion picture stream evaluator comprising a plurality ofmotion picture code evaluators according to any one of said claims 1through 5, arranged to process a plurality of motion picture streams inparallel.
 7. A billing system for a motion picture transmission servicewhich charges depending on the receiving quality of a motion picturebased on the total motion picture information amount obtained from amotion picture code evaluator according to any one of said claims 1through 5.